Unlockables

Critical Mode

New Game+

Once you've beaten the game on any difficulty, you'll be prompted that you can create a new game and carry over certain things from your past file. Things that are carried over include all Spirits you've made reset to Level 1, certain sections in the Reports including Story, Character Files, Trophies, and Glossary. The Mementos section is also fully included. Only recipes are carried over from your items.

Unlockable

How to Unlock

New Game+

Beat the game on any difficulty, create a New Game, and select Yes when asked to transfer data.

Secret Boss

Secret Ending in Theater Mode

Once you beat the game, you'll unlock Theater Mode. To get the Secret Ending, you have to get a certain amount of trophies depending on your difficulty setting.
Beginner 13
Standard 7
Proud 5
Critical 0
Next, you need to answer the three questions that were asked to Riku at the end correctly. The answers are:
1. Losing something that's important.(Option 3)
2. My friends.(Option 2)
3. To find something important.(Option 2)
Afterward, you need to unlock the Secret Message during the credits by collecting the gold letters during Sora's credit Dive. It will spell out "Secret Message Unlocked."
Once you save your end-game file and reload it, you should get a prompt saying you unlocked the Secret Ending in Theater Mode.

Secret Message in Glossary

When you bet the game and you've seen the credits, you'll go with Sora into drop mode and drop through the credits. After 2 or 3 rolls, certain letters will glow yellow/goldish, as you pick them up, a message will begin to spell on your touch screen. When you have all the letters, your touchscreen will say; "Secret Message Unlocked". This will give you an extra item for in your glossary.

Unlockable

How to Unlock

Secret Message in Glossary

Get all the glowing letters to spell "Secret Message Unlocked" and it will give you an extra item for in your glossary.

Secrets

Rank boost during Spirit creation

Any spirits you create while in a world that is currently experiencing the Risky Winds weather will have their rank boosted by one. Risky Winds also greatly increases the chance of creating the mystery monster for recipes with more than one outcome.

Enemy/Boss Tips

Secret boss fight.

Once you beat the game, Choose to save cleared game data. Once that's done, open that game file and go to traverse town. Then go to the fountain plaza. Then you will have to fight the secret boss until you beat him, or until he kills you. At first he's hard to beat. The lowest level I would fight him on is level 50. But I beat him on level 49. Try fighting him on level 60,70 or 80. If you are at that level and want to fight him, make sure that you have a lot of balloon commands in your command deck. :-)